Signal Level Meter Basics
The Signal Level Meter is probably the single most essential piece of instrumentation required for a CATV network and is often referred to as a Field Strength Meter (FSM). GAOTek offers a wide range of high performance and inexpensive TV and CATV signal level strength meters for any practical application.
What does a Signal Level Meter do?
A Signal Level Meter is used to effectively and accurately measure the analogue and digital channels of TV and satellite signal strengths. They are the preferred device choice for TV installation technicians.
When can Signal Level Meters be used?
TV Signal Level Meters are commonly used inside television and radio broadcasting equipment, in order to systematically measure and evaluate the signal strengths and power levels.
Through the field strength measurements, we are then able to have a preliminary understanding of the quality status of the equipment and network operation.
Signal Level Meters are compatible with both analogue and digital channels with both strong and comprehensive performances. They integrate a clear LCD screen with dual-channel measurement displays and high brightness operating modes to create a truly convenient and pragmatic device.
Types of Signal Level Meters
Generally, Signal Level Meters are classified into three different groups:
- CCTV Signal Level Meters: As most modern CCTV testers already come with equipped functions to program the cameras and measure a wide range of variables, only one device is required. The operator is able to test and also program the cameras from one location with a singular device, saving money and time.
- Satellite & CATV Signal Level Meters: Primarily used to test and measure the quality of TV and satellite signals, ensuring that the signal levels are delivered as required. They also go by the names of ‘Satellite Finders” and “Field Strength Meters” These devices are generally intended for use by a service technician or installer. Signal levels are measured over a specified frequency range, generally expressed in decibel-milliwatts, dBm.
Features & Functions
Signal Level Meters have multiple features and are able to complete a wide variety of tasks; here are some common features:
- Compact for easy handling and storage
- Automatic timing measurements
- Lightweight and easy to carry handheld design
- High capacity batteries for long user time
- Relatively quick charging
Signal Level Meters are also packed with multiple functions such as:
- Single and multi-channel testing
- Automatic channel power measurement
- All band scanning
- Modulation Error Ratio (MER)
- Bit Error Rate (BER)
- Measurement and Signal-to-Noise Ratio (SNR)
The above three terms are borrowed from the telecom industry for signal level and are extremely helpful for an installer/service technician to help find loose or corroded wires, lengthy cable runs, problems at the ground block, multi-switches, head end or tap
Definitions & Terms
MER: A measure used to quantify the performance of a digital radio transmitter or receiver in a communications system.
BER: The number of bit errors divided by the total number of transferred bits in a certain timer interval.
SNR: The ratio of the strength of an electrical or other signal carrying information to that of unwanted interference.
CATV Signal Level Meters are primarily used to test the TV field strength level generally by the attenuation circuit and the RF input on the device. The Signal Level Meter is equipped with a central processing unit (CPU) and uses an LCD screen to directly display all information, making operation immensely convenient for the user. Signal Level Meters would be connected to the cable from the antenna or cable provider. The antenna can be located and adjusted based on the signal level and other problems diagnosed, making these particular devices extremely easy to set-up and use.
In addition to the main signal level measurement, Signal Level Meters also have other functions such as:
- Carrier noise ratio measurement
- Sound carrier measurement
- Audio monitoring
- Spectrum measurement
Factors Affecting Selection
An excellent Signal Level Meter should ideally have a wide measurement range, high accuracy, small resolution, minimal weight and a long battery life.
The following performance factors are extremely relevant for selecting different Signal Level Meters:
- Frequency range: Signal Level Meters are available in a very wide range of frequencies for multiple different scenarios.
- Measurement speed
- Accuracy requirements: Different jobs will require Signal Level Meters with high or low accuracies.
- Calibration & Zero: If possible, obtain a Signal Level Meter that requires little to no initial calibration, or a device that does not need to be adjusted to zero.
- Signal type
- Storage capacity
- Spectrum display
- LCD screen size
Keep the below in mind specifically for CCTV Signal Level Meters:
- Pan/tilt/zoom control and testing
- Integrated multi-meter functions
- UTP cable testing functions
- NTSC/PAL video standard support
- Vpp signal amplitude measurement